Several processes are known to produce photographic papers having various patterns on the surface. One process comprises forming a pattern after conclusion of all photographic processings such as development and fixation, etc. However, this process is not suitable for mass processing and a high cost with respect to processing rate or processing apparatus, etc., is involved. A second process involves forming a pattern after application of the photographic emulsions. There are disadvantages with this process because it is not photographically suitable since a physical force is applied to the surface of the emulsion layer and there is the difficulty in production because formation of a pattern must be carried out in a dark room. A third process involves applying photographic emulsions to the support after the formation of pattern on the support. The last process is most advantageous from the standpoint of the work involved.
Suitable supports for photographic papers are papers, the both sides of which are coated with polyolefin in order to provide a waterproof property. In order to form a pattern on the surface of the support, generally a process is employed which comprises pressing a cooling roll having a desired engraved pattern onto a paper support where extrusion coating of polyolefin on the paper support is used.
Recently, attempts have been made to provide a waterproof property to the support by applying an organic compound having an unsaturated bond capable of being polymerized upon irradiation of electron beams instead of a polyolefin to a paper support and hardening the compound by irradiation with electron beams (Japanese Patent Applications (OPI) Nos. 27257/82 (corresponding to U.S. Pat. No. 4,384,040, hereinafter the same), 30830/82 (U.S. Pat. No. 4,364,971) and 49946/82 (U.S. Patent Application Ser. No. 300,526, 9-9-81) (the term "OPI" as used herein refers to a "published unexamined Japanese patent application")).
In this process, the formation of a pattern, such as forming a silk fabric pattern or a mat pattern, etc., is not known. Further, a process for producing a glossy surface is described in the above-described Japanese Patent Application (OPI) No. 30830/82. This process comprises irradiating the compound with an electron beam from the back of a paper support, where a glossy surface is pressed against the unhardened coated surface to harden the compound and thereafter separating the hardened surface from the molding surface. This process has the disadvantage that lateral defects occurs in separating the hardened coated surface from the molding surface. The term "lateral defects" used in this specification is a wave-like uneven thickness of the coating layer in the longitudinal direction of the web which occurs due to a small difference in thickness of the coated surface, and a fatal disadvantage in quality of the photographic paper arises. Further, in this process, since an electron beam is applied through the paper support and this results in a great loss, an electron beam irradiation apparatus having a large capacity must be used. Consequently, the equipment investment becomes great.